Warp thread brakes for circular looms



Jan. 1, 1963 -c. CHRISTIANSEN ETAL 3,071,153

WARP THREAD BRAKES FOR CIRCULAR LOOMS Filed Nov. 30, 1959 Away-n (fn'h x/ Q United rates Patent U f WARP THREAD BRAKES FOR ELKCULAR LGQMS Christian Qhristiansen, Gslo, and Einar Hpya, Manda Norway, assignors to Mandais Reberhane Qhristiansen dz Co, A/S, Mandal, Norway Filed Nov. 30, 1959, Ser. No. 856,ti41 Claims priority, application Norway Dec. 5, 1953 4 Claims. Ci. 139-13) The present invention relates to improvements in a device intended for use as a brake to the run of the warp threads in circular looms in particular such circular looms which are adapted for the Weaving of hoses, such brake device comprising parallel rods about which the warp threads are passed in approximately S-formation, the position of such rods being variable relatively to the direction of the advance movement of the warp threads.

Devices of this type are previously known, wherein a pair of straight rods at their ends are mounted in supports which may be turned about an axis situated midways between the rod axes and extending parallel to the same. By an angular movement of such supports, the warp threads passing the rods are caused to contact the two rods along greater or smaller arcs of the circumference of the same, to the effect that the braking effect on the threads, which is due to the friction between the rod surfaces and the threads advancing in their direction of length may be varied by adjustment of the rod support about the axis of rotation of the same.

Each warp thread is carried to and from the braking rods through holes in guide rods extending concentrically to the axis of the loom, the said hole thereby extending at a suitable angle underneath and above the brake rods, respectively. Hereby, the straight brake rods referred to are extending according to chords to the circles defined by the pair of guide rods. According to the length of the brake rods and the radius of the guide rod pair, there will be a greater or smaller difference in the direction of the threads running to and away from the brake rods, dependent upon the positions of such threads, near to the ends or to the middle of the chord defined by each brake rod. The difference in braking effect thereby produced is, it is true, very small per se, but may be of importance in cases in which high quality requirements are put on the product to be manufactured on the loom.

According to the present invention, therefore, also the brake rods are formed as arcs of circles which are concentric to the guide rods about the axis of the loom. Hereby not only the difference in brake effect mentioned above is avoided, but a more even run of the warp threads is obtained, in addition to an improvement in the appearance of the loom.

In order, hereby, to obtain that the brake effect is constant all along the length of the curved rods, irrespectively of the angular position at which they are set relatively to the direction of advance of the warp threads, the curved brake rods forming a pair are mounted at either end in a common support which is turnable about an axis extending at right angles to the radius of curvature of the rods and provided with bores, each receiving a rod end and extending parallel to the axis of rotation of the mounting. Thus, when such a support is turned about its axis, the two rods mounted therein are forced to perform an absolute parallel displacement with respect to members 2 and 3, without any rotation about the axis of the sup port to the effect that the inlet and outlet conditions remain equal to all warp threads distributed along the whole length of the rods, independently of the angular position of the support.

As mentioned, the brake rods are divided into lengths along the circumference of the loom, such length being, as previously known, supported in the vertical framework of the loom.

Patented Jan. 1, 1963 The two bore receiving the rod ends in each support may then suitably be so arranged that part of their circumferential surface opens into the bearing surface of the support, to the effect that part of the surface of each rod contacts the support bearing and is subjected to friction against the same. When turning the support, the rod surface consequently will tend to lag behind in the turning movement, thereby causing the rod to perform an oppositely directed turning movement relatively to the support, but no rotational movement about the support.

For the purpose of locking the rods in the support, the latter may be provided with a clamping collar encircling the support and thereby also contacting the exposed portions of the circumferential surface of each rod, such clamping collar being adapted to be released when the support is to be turned.

The accompanying drawing illustrates schematically how the invention may be performed. Hereby it is to be noted that all parts are deleted which are not essential to the understanding of the invention.

FIGURE 1 is a view of a part, as seen from above, of the circumference portion of a circular loom incorporating the brake rods according to the invention.

FIGURE 2 is a sectional view taken at right angles to the axis direction of the rods, i.e. radially to the loom.

FIGURE 3 is an axial sectional view of a brake rod support, taken along the line ili-III of FIGURE 4.

FIGURE 4 is a sectional view along the line lV-IV of FIGURE 3.

In the drawing, 1 is the vertically extending framework parts of a circular loom of conventional construction, While 2 and 3 are the top and bottom guide rods, respectively, for the warp threads 4, FIGURE 2, each Warp thread being passed through individual holes 5 and 6, respectively, in the two rods.

Between the two rods 2 and 3 a pair of rods 7 and 8 are arranged. As indicated in FIGURE 1, each such rod 7, 8 extends along a circle about the axis of the loom in a plane at right angles to such axis. As shown in FIGURE 2, each warp thread is passed in approximately S-forrnation about the rods 7 and 8 between the holes 5 and 6 of the rods 2; and 3. By so changing the relative position of the rods 7 and S that a line joining their centres, FIG- URE 2, performs an angular movement, the angles of encirclement of the thread relatively to the two rods may be varied and thereby the braking effect of the rods on the threads due to the friction between the threads and the rod surfaces.

The rods '7 and 8 are at each end mounted in a framework part 1 by means of a support 9. FIGURES 3 and 4 illustrate an embodiment of a pair of such supports, each adapted to mount one pair of two pairs of brake rods 7 and 8 meeting in a framework part 1.

Each support 9 consists of a cylindrical member it which is received in a corresponding bore in the framework 1, and having a flange portion 11 extending at right angles to the axis of the member 10 and contacting a side surface of the framework 1. Each support is provided with a pair of bores 12- and 13 extending parallel to the axis of the member 10 and each adapted closely to receive an end of a rod 7 and 8, respectively. Each bore is so situated in the member 10 that the axis of the same is spaced from the circumference of the member It by a distance which is smaller than the radius of the bore, to the effect that a portion of the circumferential surface of each rod is exposed in the circumferential surface of the member 10. The circumferential surface of the member if) is provided with an annular recess receiving a clamping collar 14, so situated as to contact the exposed portions of the surfaces of the rods 7 and 8 of such width as also to enclose the second support 9 mounted in the same framework part 1. The clamping collar 14 is split and provided with projecting ears 15 provided with aligned bores adapted to receive a screw threaded bolt 16 extending to the external surface of the part 1, so as to enable an adjustment of the clamping efiect of the collar 14 by a setting of the'screw bolt 16.

When the angular position of the line joining the axes of the rods 7 and 8 relatively to the axis of the support is to be changed for the purpose of adjusting the brake effect to which the warp threads are subjected, the screw 16 is slightly unscrewed, the two supports at both ends of such rods are turned through the desired angle and the screw 16 is reset. During such turning movement of the supports, the rods 7 and 8 are, as described above, maintaining their axes in parallel relation without either performing any angular movement about its respective axis.

We claim:

1. A warp thread braking device for use in a circular loom comprising a pair of mutually parallel arcuate rods about which the warp threads may be passed in approximately S-forma-tion, and means supporting the two rods along arcs of circles which are concentric about the axis of the loom, said rods being divided into lengths, said supporting means including common support members engaging the adjacent ends of two mutually parallel arcuate rod lengths, bearing means supporting each said support member on the loom for rotary adjustment about a pivotal axis normal to the 100m axis, each said support member being provided with bores spaced from said pivotal axis, each rotatably receiving one rod end and extending parallel to the pivotal axis of the support member.

2. A device as claimed in claim 1, characterized in that support members adapted to mount the adjacent ends of two adjacent pairs of rod lengths are rigidly interconnected.

3. A device as claimed in claim l, characterized in that the support members are cylindrical and the axes of the rod end receiving bores therein are situated at a distance from the circumferential surface of the support member which is slightly less than the radius of such bores, the said ends of the respective rod lengths engaging said bearing means and causing rotation of said lengths relative to the support means, incident to rotary adjustment of the support means.

4. A device as claimed in claim 3, characterized in that each bearing means comprises a clamping collar, and selectively operative means for tightening and loosening said collar.

References @ited in the file of this patent UNITED STATES PATENTS 399,872 Gibbs Mar. 19, 1889 2,327,987 Balsach Aug. 31, 1943 2,603,240 Christiansenet al July 15, 1952 2,774,550 Pieper Dec. 18, 1956 FOREIGN PATENTS 1,154,098 France Oct. 28, 1957 

1. A WARP THREAD BRAKING DEVICE FOR USE IN A CIRCULAR LOOM COMPRISING A PAIR OF MUTUALLY PARALLEL ARCUATE RODS ABOUT WHICH THE WARP THREADS MAY BE PASSED IN APPROXIMATELY S-FORMATION, AND MEANS SUPPORTING THE TWO RODS ALONG ARCS OF CIRCLES WHICH ARE CONCENTRIC ABOUT THE AXIS OF THE LOOM, SAID RODS BEING DIVIDED INTO LENGTHS, SAID SUPPORTING MEANS INCLUDING COMMON SUPPORT MEMBERS ENGAGING THE ADJACENT ENDS OF TWO MUTUALLY PARALLEL ARCUATE ROD LENGTHS, BEARING MEANS SUPPORTING EACH SAID SUPPORT MEMBER ON THE LOOM FOR ROTARY ADJUSTMENT ABOUT A PIVOTAL AXIS NORMAL TO THE LOOM AXIS, EACH SAID SUPPORT MEMBER BEING PROVIDED WITH BORES SPACED FROM SAID PIVOTAL AXIS, EACH ROTATABLY RECEIVING ONE ROD END AND EXTENDING PARALLEL TO THE PIVOTAL AXIS OF THE SUPPORT MEMBER. 